Introduction Branchial cleft cysts are common congenital neck anomalies resulting from incomplete obliteration of the branchial apparatus. An aberrant right subclavian artery (ARSA), present in approximately 1% of individuals, typically follows a retroesophageal course and is associated with a non-recurrent laryngeal nerve (NRLN). We describe a rare coexistence of a branchial cleft cyst and an ARSA, underscoring the importance of recognising this vascular variant in surgical planning. Case Description A patient presented with a right-sided neck swelling. Contrast-enhanced CT imaging revealed a cystic lesion consistent with a branchial cleft cyst. Incidentally, an aberrant right subclavian artery with a retroesophageal course was identified. Discussion Recognition of an ARSA prior to neck surgery is critical because of its association with a non-recurrent laryngeal nerve (NRLN). In this case, the cyst was located ipsilateral to the ARSA, increasing the likelihood of encountering this nerve variant. Awareness of these associations is essential to minimise the risk of nerve injury during surgical dissection. Conclusion This case highlights the importance of thorough preoperative imaging and anatomical assessment to identify vascular variants that may significantly influence surgical planning and operative safety.